Errata for Invasion of the Alien Ducks

This was the first material that I produced which was suitable for wider distribution. It's a MakeCode Arcade Blocks worksheet and is suitable for anyone that has some experience of blocks programming. The PDF is available here and is licensed under the Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.

To view a copy of this license, visit https://creativecommons.org/licenses/by-nc-sa/4.0/. The materials are designed to be used in printed form. As this is over 40 pages long and image heavy, I have published it on Amazon where you can buy a printed copy for £4.50.

After I completed the book, I discovered a bug in the code. I can't modify the source material that you can buy on Amazon without increasing the price to fit with Amazons updated pricing structure. Therefore I decided to keep the book as is an provide the fix here.

Step 6 - Creating a function to descend sprites

After completing step 6, shooting a Duck or Apple that is on the top row will result in the "Program Error: sim error: failed to cast on null" being reported. The cause is due to the placement of the final 4 blocks in the outer if block highlighted in the below screen shot.

The blocks need moving into the inner if block as shown in this screen shot.